<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>伪类选择器</title>
    <style>
        a {
            text-decoration: none;
        }

        a:link {
            color: #333;
        }

        a:visited {
            color: orange;
        }

        a:hover {
            color: skyblue;
        }

        a:active {
            color: red;
        }

        input {
            width: 200px;
            height: 80px;
        }
        
        input:focus {
            background-color: skyblue;
        }
    </style>
</head>
<body>
   <a href="#1">小猪1</a>
   <a href="#2">小猪2</a>
   <a href="#3">小猪3</a>
   <a href="#4">小猪4</a>
   <a href="#5">小猪5</a>
   <br>
   <input type="text">
   <input type="text">
   <input type="text">
</body>
</html>